The hydraulic fracturing technology has been widely used in the development of oil and gas fields as a major measure for increasing production of oil and gas wells and augmented injection of water wells, and has made important contributions to stable production and stable injection of oil and gas fields. Hydraulic fracturing refers to pumping high-viscosity pre-flush fluid into a target reservoir, forming fractures at high pressure and extending the fractures, and then pumping sand-carrying fluid mixed with a proppant, wherein the sand-carrying fluid can continue to extend the fractures, and at the same time carry the proppant deep into the fractures. It is best to break and degrade the fracturing fluid into low-viscosity fluid which then flows to the bottom of the well and later flows back, thereby leaving a flow channel with high flow conductivity formed by the proppant supporting the fracture wall in the formation to facilitate flowing of oil and gas from the far-field formation to the bottom of the well.
However, from the point of view of the hydraulic fracturing technology and its development, all fracturing technologies are currently based on the process of forming fractures with a fracturing fluid, then injecting a solid proppant to hydraulic fractures, and supporting the fractures to keep them open, thereby obtaining a flow channel with high flow conductivity. In 2010, Schlumberger proposed that the flow conductivity of fractures in a HIWAY high-speed channel was not affected by the permeability of a proppant. Compared with the conventional fracturing technology, this technology also needs to inject a solid phase proppant into a formation, and the process is complicated to implement.
During the construction process, the injection of the solid proppant can easily cause sand removal, sand plugging, and injection failure, so the construction cannot achieve the desired effect, and even cause blockage in a wellbore with sand. Petroleum workers have been working on the research of low-density and high-strength proppant for the purpose of making the proppant easy to inject. Whatever it is a low-density or high-density proppant, the solid proppant needs to be injected from the wellhead into the formation. However, the solid proppant in the conventional sand-blast fracturing process may cause problems such as difficult injection and difficult injection. In order to improve the fracturing construction effect, the present invention provides a new construction process—a fracturing process without a proppant, which specifically comprises: injecting a phase-changeable supramolecular fracturing fluid based on supramolecular self-assembly into the formation, wherein the fracturing fluid on the ground is a flowable liquid phase, and the flowable liquid phase is formed into a solid phase 20-240 min after being injected into the formation at a formation temperature, so as to support the fracture wall, thereby forming a channel with high flow conductivity in the formation.